The ornamental design for a devicecover, as shown and described.
FIG. 1 is a front perspective view of a device cover in a closed state;
FIG. 2 is a back perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a back view thereof;
FIG. 5 is a left-side view thereof;
FIG. 6 is a right-side view thereof;
FIG. 7 is a top view thereof;
FIG. 8 is a bottom view thereof;
FIG. 9 is a front perspective view of the device cover in an opened state thereof; and,
FIG. 10 is a back perspective view of the device cover in the opened state.
The short dash broken lines depict portions of the device cover that form no part of the claimed design. The long dash broken lines depict stitching on the surface of the device cover that forms no part of the claimed design. The dot-dash broken lines represent boundaries of the claimed device cover and form no part of the claimed design.